M. Night Shyamalan’s Split is a solid-ish horror-exploitation flick with a strong performance from James McAvoy, who plays Kevin, a man with 23 distinct personalities. While Kevin’s multiple personalities have been able to co-exist and even thrive in recent years, an unsettling incident awakens two of Kevin’s more evil personalities — Dennis and Patricia — who conspire with Kevin’s 9-year-old personality, Hedgwig, to abduct three young women, Casey (Anya Taylor-Joy), Marcia (Jessica Sula) and Claire (Haley Lu Richardson). Dennis and Patricia hold the three women hostage in a large basement for reasons that are best left unexplained. Meanwhile, Kevin’s other personalities attempt to seek aid from their therapist, Dr. Karen Fletcher (Betty Buckley).

Split plays a bit like last year’s 10 Cloverfield Lane, only instead of being held hostage by John Goodman, the three women are held hostage by several different personalities of one man. It’s intermittently intense, occasionally funny, very well shot, and mostly engrossing, despite its many lapses in logic. It’s the kind of inexpensive, entertaining horror movie we’ve mostly come to expect from Blumhouse Pictures and more recently, Shyamalan, with the excellent, self-contained horror thriller The Visit.

But there’s something else afoot here. It’s not exactly an M. Night Shyamalan twist, but a nod toward a longer game and the less viewers know about it, the better. The payoff for the film doesn’t come until the last 30 seconds, and I’m still not sure how I feel about it. I’m evenly split between excitement for a future prospect, and annoyed that a nifty, intimate little horror flick is actually an entry point into something bigger.

Still, Split mostly works when the focus is on McAvoy. The idea of a character with 23 personalities sounds exhausting, but McAvoy pulls it off so well that we’re sad we don’t get to spend much time with about 15 of those personalities. The exploitative nature of the film feels icky as hell, and the threat of sexual abuse is unsettling even if — in the present timeline — it’s a red herring (and in flashbacks, pointless and predictable). Moreover, the female characters are mostly wasted, treated as disposable plot devices, even moreso once the ending is revealed and we discover that their stories existed only to serve a larger one.

However, beyond saying that it’s worth watching, especially for fans of Shyamalan’s earlier work, and piquing your interest in Split, I don’t feel comfortable saying much more for fear of spoiling the surprise. It is quite a surprise, but your mileage may vary on whether it’s a welcome one or not.

Dustin is the founder and co-owner of Pajiba. You may email him here or follow him on Twitter.